Ce doped lanthanum tri-bromide SPET scanner for molecular imaging

The availability of LaBr3:Ce crystals from St. Gobain has started various investigations in the field of medical imaging, in particular in PET, SPECT and Compton camera systems. At present LaBr3:Ce crystals are available in a continuous shape covering up to 10×10 cm2 with a thickness of 1 cm, in contrast, serious concerns are arising in pixellated manufacturing. With the aim of verifying the potentials introduced by LaBr3:Ce for SPET imaging, two small γ cameras based on Anger camera principle have been assembled and imaging performances were compared. Two crystals of LaBr3:Ce and NaI(Tl) with the same detection area (5×5 cm2) and thickness of 5 and 1.5 mm, respectively were been integrally assembled with a H8500 Hamamatsu flat panel PMT. Through the thicker crystal, the LaBr3:Ce camera showed superior imaging and detection performances at 140 keV compared with the NaI(Tl) one, with 0.9 mm FWHM intrinsic spatial resolution, 8% FWHM energy resolution and 80% intrinsic detection efficiency.